Optimisation of Fibre-Reinforced Hybrid Composites Under Combined Loading

Fibre-reinforced hybrid composites offer an effective balance between strength, weight, and cost by combining multiple fibre types within a single matrix. This study focuses on optimising the design of carbon/glass fibre-reinforced hybrid composites under combined bending and torsional loading using finite element analysis (FEA) and response surface methodology. Twelve different layup configurations, including sandwich and non-sandwich hybrid designs, were analysed to identify the optimal ply angles and fibre volume fractions that maximise failure load while minimising material cost and density. The results reveal that sandwich-type layups, such as [C3G]S, [C2G2]S, and [CG3]S, demonstrate superior strength-to-weight performance, achieving failure loads exceeding 300 N. The study also confirms that optimal ply angles range from 12° to 30°, depending on the layup configuration, and that increasing the carbon fibre volume fraction generally enhances failure load, though an optimal balance with glass fibres must be maintained. The findings provide valuable design guidelines for engineers seeking to tailor hybrid composites for aerospace, automotive, and structural applications. Future work should focus on experimental validation and extending the analysis to additional loading conditions, such as impact and fatigue, to further improve the robustness of hybrid composite structures.